What function does the HER2 receptor serve in breast cancer?

The HER2 receptor plays a critical role in the development and progression of certain types of breast cancer, particularly those characterized by HER2 gene amplification or overexpression. When HER2 is overexpressed, it leads to the activation of various signaling pathways that promote cell proliferation, survival, and migration. This aberrant signaling contributes significantly to aggressive tumor growth and poor prognosis in patients with HER2-positive breast cancer.

The overexpression of HER2 results in an increase in the number of active receptors on the cell surface, which enhances the signaling cascades that drive cellular processes associated with cancer, such as rapid cell division and resistance to apoptosis. Therefore, understanding this function of HER2 is crucial in both diagnosing HER2-positive breast cancer and developing targeted therapies, such as monoclonal antibodies, that specifically target the HER2 protein to inhibit its activity and slow down tumor growth.